20140119.2314

In my last post I showed how to get openCV 3 up and running under OSX Mavericks.

After playing with the GUI-Features in Python I settled to use GTK for my project. As it turns out, there is a project called gtk+ or gtk-osx which will allow you to bundle an App that runs on OSX without the need to have X11 installed.

Great! I thought, everything went fine, building gtk-osx with python 2.7, building ffmpeg with all its GPL codecs, even building gfortran, which is needed to build scipy was a piece of cake after realizing, that you need to link in gmp, cpfr, cpm, isl, and cloog symbolicly into the source directory of gcc - otherwise it will just crash while making bootstrap. TBB and Eigen3 also built straight forward.

But then I tried scipy. Numpy was there, gfortran was there, all other prerequisites that could have been neccessary were there, but it simply refused to build. Scipy is not a real dependency for openCV, but it is a very useful math lib, so it is kind of a dependency for me to have fun.

Google did not help me a lot here, but in the end I got it built doing the following:

In the jhbuild shell environment I first set my PYTHONPATH to only consist of my local gtk+ python.

20121216.1754

I built a wonderful 12 TB RAID 50 NAS and it runs smooth and quiet, but consumes around 70 watts under load, which is still good for 6 Hitachi enterprise class drives. So I thought about sending these 6 drives to standby after 1 hour of silence on their bus:

First install hdparm and set up the config-file ( we are on Debian Squeeze as root here ):

Looks good so far, but after 3 hours of inactivity the drives are still active. Reducing the value to 240 ( 20 minutes ) works great, so whats wrong here?

Stopping all services and testing them one by one reveals, that smartd causes the drives to stay awake.

I edited /etc/smartd.conf to contain "-n standby":

DEVICESCAN -n standby ...

That should prevent spinning discs up when they are in standby - but that did not solve the problem, because the drives were not spun down when smartd checked them, so it accessed them and the spindown timer was reseted.

In addition to the "-n standby" option I had to increase the check-interval in /etc/default/smartmontools to something slightly above my spindown timer:

Now all 6 drives fall asleep after one hour saving me around 40 watts. My OS is installed on a separate SSD, so the drives only wake up when the NAS serves data, or backs up my servers. S.M.A.R.T.-checks are executed less often, but that should be no problem.

20101220.0927

Recently a big wave of Spam splashed into my comments-section. The easiest way to deal with this was to delete all comments. If I accidentally deleted a real comment, please feel free to post it again. I have configured the Spam-filter to be more progressive and delete Spam instead of save it for moderation. If you want to be sure, that your comment is not treated as Spam, then please send it without hyper-links and stuff like "Awesome post yadda yadda yadda"

20100420.1337

I use Dovecot and roundcube as a web-portal. It works great, but i could not get the actual autocreate-plugin to work as my Dovecot is still Version 1.0.something. I tried to compile the plugin but the mail-namespace.h was missing somehow (yes, I got the sources first). Upgrading to the lenny-backports version of Dovecot did not work either.

Well autocreating a directory-structure worked perfectly with the plugin provided for that version, but autosubscription failed.

After messing with that issue for a while I decided to script that feature myself. I use Maildir, so I only need to get the autosubscribe-Variables defined in the dovecot.conf file into the subscriptions file in the user-specific Maildir.

I coded this little bashscript and placed it into my Dovecot-install-directory (do not forgot chmod +x it):

#!/bin/bash

# first check if this is called by a user logging in, and not by dovecot startup
if [ "$USER" != "dump-capability" ]
then

20100412.1743

... That is because of some (actually a lot of) work, that needs to be done right now. After spending the whole day in front of a display, tricking around with source code and bytes, I do not want to spend the evening in front of another display...

Well I am sorry for the readers, and yes there are some pretty cool things going on - i.e. time-tracking for console-monkeys is expected to come soon - but, ATM I am not in the mood to blog stuff...

20091215.1057

I finished the work on my terminal-based organizer. It includes a todo-list, a simple event-calendar and a logging-function to keep track of actions you need to remember. The event-calendar supports whole-day events, like birthdays aswell as yearly repetition.
A monthly repetition mode is planned.
It is mainly based on bash-scripting and uses awk, grep, sed and a bit of perl, is colored and the best of all: it synchronizes between diffrent linux-pc's and mac's using a svn-repository.

There are some configuration options available, for example which domain to ping to check the internet connection, the editor to use for editing events and the logfile and an interval for how long the last svn-update is used before updating again.

20091206.0029

Grind down your keyboard and you will learn to type in no time. The trick is: if you can't see the letters, you stop looking and start guessing. By and by you guess better and better - soon you type 100+ keystrokes per minute. -- Don't believe me? Try it!

But before you buy a dasKeyboard, get some sandpaper (grain: 80, 240, 600 and 1000), a starbucks-coffee-mug (that one worked perfectly for me, but you can use any cylindrical object, that fits the curve of your keys) and do it yourself.
Hold the sandpaper tight around your coffee-mug and grind the keys. Start by doing a few strokes with the 80 grain, until the letter has gone. Then polish it up step by step. Finally use some water with the 1000 grain and you get a very nice finish.
You can do it line by line to optimize your workflow. First grind all keys over the 80 grain paper, then the 240, and so on...
Be carefull with the F and J keys, they usually have some small bulge, to feel the right position for your hands. Special keys like return, shift, ctrl and the spacebar (oh yeah, that one definetly) need a special treatment - and some skill to look good in the end - but I am sure, you will advance and succeed.
I used an old apple wireless keyboard (yeah, the white ones, which fill up with crumbs over time) with spanish layout, therefore it was quite cheap on ebay.